Optical technology using space light modulator such as DMD (Digital Micro mirror Device) or the like have been used in a projector.
In digital light processing, for example, a DMD includes a plurality of micro mirrors which are arranged as an array. The DMD is irradiated with light and the reflection light from the DMD is enlarged by lens or the like to be projected, so that an image is displayed. Conventionally, white light from an irradiation lump or the like as an optical source is injected into a color foil with a circular shape to be separated in this method. Color filters with red (R), green (G) or blue (B), respectively, are arranged in the color foil. The color light separated by the mirror in the DMD is transformed in order into a color image. In this step, the color light is driven in time division with synchronization to a rotation of a color foil.
In the projector, lifetime, deterioration, exothermic, consumption power or the like are pointed out as an important problem. Further, downsizing or the like of the optical source has also been demanded. Recently, semiconductor emission elements with RGB colors, for example, an emission diode, laser diode or the like have been used instead of irradiation lumps. Therefore, downsizing of the semiconductor emission elements has been developed.
Especially, when a semiconductor emission element is installed in a projector with a volume disposed on a hand or put in a pocket for carrying with convenience, it has been desired to product not only downsizing of the optical source but a semiconductor emission element with high emission.
Furthermore, it has been expected by downsizing to extend to application to a small desktop-type projector, back projection-type TV or the like, for example, other than a digital handy assistance, a cell phone, a PC or the like, for example.